Ar cle 490 Where the par es conclude a contract in the form of a wri en agreement, the contract is formed at the me when the par es all sign, stamp, or put their ngerprints on the memorandum. Prior to signing, stamping, or pu ng their ngerprints thereon, where one of the par es has already performed the principal obliga on and the other party has accepted the performance, the contract is formed at the me of such acceptance. Where a contract is required to be concluded in wri ng in accordance with laws or administra ve regula ons or agreed by the par es and the par es fail to make the contract in wri ng, if one of the par es has already performed the principal obliga on and the other party has accepted the performance, the contract is formed at the me of such acceptance. Ar cle 491 Where the par es conclude a contract in the form of a le er, data message, or the like, and a con rma on le er is required to be signed, the contract is formed when the con rma on le er is signed. Where the informa on about goods or services published by a party via informa on network, such as internet, conforms to the condi ons for an o er, unless otherwise agreed by the par es, a contract is formed at the me when the other party chooses such product or service and successfully submits the order. Ar cle 492 The place where an acceptance becomes e ec ve is the place where the contract is formed. Where a contract is concluded in the form of data message, unless otherwise agreed by the par es, the recipient’s principal place of business is the place where the contract is formed; in the absence of a principal place of business, the recipient’s domicile is the place where the contract is formed. Ar cle 493 Where the par es conclude a contract in the form of a memorandum of contract, unless otherwise agreed by them, the place where the contract is nally signed, stemped, or ngerprinted is the place where the contract is formed. Ar cle 494 Where the State issues a State purchase order or a mandatory assignment in accordance with the needs such as emergency and disaster relief, pandemic preven on and control, or the like, the persons of the civil law concerned shall conclude a contract in accordance with the rights and obliga ons provided by the relevant laws and administra ve regula ons. The party that has an obliga on to make an o er in accordance with the provisions of laws and administra ve regula ons shall make a reasonable o er in a mely manner. The party that has an obliga on to make an acceptance in accordance with the provisions of laws and administra ve regula ons shall not reject the reasonable request of the other party to conclude a contract. Ar cle 495 A le er of subscrip on, le er of order, and le er of reserva on, and the like, in which the par es agree to conclude a contract within a certain period of me in the future, cons tutes a preliminary contract. Where one of the par es fails to perform the obliga on to conclude a contract agreed in the preliminary contract, the other party may request such party to bear the liability for breach of the preliminary contract. Ar cle 496 A standard clause refers to a clause formulated in advance by a party for the purpose of repeated use which has not been nego ated with the other party when concluding the contract. Upon concluding a contract, where a standard clause is used, the party providing the standard clause shall determine the par es’ rights and obliga ons in accordance with the principle of fairness, and shall, in a reasonable manner, call the other party's a en on to the clause concerning the other party’s major interests and concerns, such as a clause that exempts or alleviates the liability of the party providing the standard clause, and give explana ons of such clause upon request of the other party. Where the party providing the standard clause fails to perform the aforemen oned obliga on of calling a en on or giving explana ons, thus resul ng in the other party’s failure to pay a en on to or understand the clause concerning his major interests and concerns, the other party may claim that such clause does not become part of the contract. ti ti ti ff ti ti ti ti tt ff ti fi ti ti fi ti ti ti ff tt ti ti ti tt ti tt ti ti ti fi ti ti fi tt ti ff ff ti ti ti tt ti ti ff ff tt ti ti tt ti ti ti ti ti ti ti ti fi ti ti ti ti ti ti ti ti ti ti ti tti tt tt ff ti ti ti ti ti ti ti ti ti fi ti ti ti ti ti ti ti ti 54 ff ti Ar cle 489 Where an acceptance makes a non-material altera on to the o er, the acceptance shall be e ec ve and the content of the contract shall be as altered by the acceptance, unless the o eror objects in me, or the o er indicates that an acceptance may not make any altera on to the content of the o er.